cp sql/ from GNU Taler exchange

include/sql/0002-refunds.sql

@@ -0,0 +1,162 @@
+--
+-- This file is part of TALER
+-- Copyright (C) 2014--2023 Taler Systems SA
+--
+-- TALER is free software; you can redistribute it and/or modify it under the
+-- terms of the GNU General Public License as published by the Free Software
+-- Foundation; either version 3, or (at your option) any later version.
+--
+-- TALER is distributed in the hope that it will be useful, but WITHOUT ANY
+-- WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
+-- A PARTICULAR PURPOSE.  See the GNU General Public License for more details.
+--
+-- You should have received a copy of the GNU General Public License along with
+-- TALER; see the file COPYING.  If not, see <http://www.gnu.org/licenses/>
+--
+
+CREATE FUNCTION create_table_refunds(
+  IN partition_suffix TEXT DEFAULT NULL
+)
+RETURNS VOID
+LANGUAGE plpgsql
+AS $$
+DECLARE
+  table_name TEXT DEFAULT 'refunds';
+BEGIN
+  PERFORM create_partitioned_table(
+    'CREATE TABLE %I'
+      '(refund_serial_id BIGINT GENERATED BY DEFAULT AS IDENTITY'
+      ',coin_pub BYTEA NOT NULL CHECK (LENGTH(coin_pub)=32)'
+      ',batch_deposit_serial_id INT8 NOT NULL'
+      ',merchant_sig BYTEA NOT NULL CHECK(LENGTH(merchant_sig)=64)'
+      ',rtransaction_id INT8 NOT NULL'
+      ',amount_with_fee taler_amount NOT NULL'
+    ') %s ;'
+    ,table_name
+    ,'PARTITION BY HASH (coin_pub)'
+    ,partition_suffix
+  );
+  PERFORM comment_partitioned_table(
+     'Data on coins that were refunded. Technically, refunds always apply against specific deposit operations involving a coin. The combination of coin_pub, merchant_pub, h_contract_terms and rtransaction_id MUST be unique, and we usually select by coin_pub so that one goes first.'
+    ,table_name
+    ,partition_suffix
+  );
+  PERFORM comment_partitioned_column(
+     'Identifies ONLY the merchant_pub, h_contract_terms and coin_pub. Multiple deposits may match a refund, this only identifies one of them.'
+    ,'batch_deposit_serial_id'
+    ,table_name
+    ,partition_suffix
+  );
+  PERFORM comment_partitioned_column(
+     'used by the merchant to make refunds unique in case the same coin for the same deposit gets a subsequent (higher) refund'
+    ,'rtransaction_id'
+    ,table_name
+    ,partition_suffix
+  );
+END
+$$;
+
+
+CREATE FUNCTION constrain_table_refunds (
+  IN partition_suffix TEXT DEFAULT NULL
+)
+RETURNS void
+LANGUAGE plpgsql
+AS $$
+DECLARE
+  table_name TEXT DEFAULT 'refunds';
+BEGIN
+  table_name = concat_ws('_', table_name, partition_suffix);
+  EXECUTE FORMAT (
+    'CREATE INDEX ' || table_name || '_by_coin_pub_index '
+    'ON ' || table_name || ' '
+    '(coin_pub);'
+  );
+  EXECUTE FORMAT (
+    'ALTER TABLE ' || table_name ||
+    ' ADD CONSTRAINT ' || table_name || '_refund_serial_id_key'
+    ' UNIQUE (refund_serial_id) '
+    ',ADD PRIMARY KEY (batch_deposit_serial_id, coin_pub, rtransaction_id) '
+  );
+END
+$$;
+
+
+CREATE FUNCTION foreign_table_refunds ()
+RETURNS void
+LANGUAGE plpgsql
+AS $$
+DECLARE
+  table_name TEXT DEFAULT 'refunds';
+BEGIN
+  EXECUTE FORMAT (
+    'ALTER TABLE ' || table_name ||
+    ' ADD CONSTRAINT ' || table_name || '_foreign_coin_pub'
+    ' FOREIGN KEY (coin_pub) '
+    ' REFERENCES known_coins (coin_pub) ON DELETE CASCADE'
+    ',ADD CONSTRAINT ' || table_name || '_foreign_deposit'
+    ' FOREIGN KEY (batch_deposit_serial_id) '
+    ' REFERENCES batch_deposits (batch_deposit_serial_id) ON DELETE CASCADE'
+  );
+END
+$$;
+
+
+CREATE OR REPLACE FUNCTION refunds_insert_trigger()
+  RETURNS trigger
+  LANGUAGE plpgsql
+  AS $$
+BEGIN
+  INSERT INTO exchange.coin_history
+    (coin_pub
+    ,table_name
+    ,serial_id)
+ VALUES
+     (NEW.coin_pub
+    ,'refunds'
+    ,NEW.refund_serial_id);
+  RETURN NEW;
+END $$;
+COMMENT ON FUNCTION refunds_insert_trigger()
+  IS 'Automatically generate coin history entry.';
+
+
+CREATE FUNCTION master_table_refunds()
+RETURNS VOID
+LANGUAGE plpgsql
+AS $$
+BEGIN
+  CREATE TRIGGER refunds_on_insert
+    AFTER INSERT
+     ON refunds
+     FOR EACH ROW EXECUTE FUNCTION refunds_insert_trigger();
+END $$;
+
+
+INSERT INTO exchange_tables
+    (name
+    ,version
+    ,action
+    ,partitioned
+    ,by_range)
+  VALUES
+    ('refunds'
+    ,'exchange-0002'
+    ,'create'
+    ,TRUE
+    ,FALSE),
+    ('refunds'
+    ,'exchange-0002'
+    ,'constrain'
+    ,TRUE
+    ,FALSE),
+    ('refunds'
+    ,'exchange-0002'
+    ,'foreign'
+    ,TRUE
+    ,FALSE),
+    ('refunds'
+    ,'exchange-0002'
+    ,'master'
+    ,TRUE
+    ,FALSE);